Imidazolylpyridine therapeutic agents

Abstract

A series of 2-substituted-4-(4-imidazolyl)pyridines and the pharmaceutically acceptable acid addition salts thereof as histamine H2-receptor inhibitors for controlling gastric acidity.

We claim: 
     
       1. A compound selected from the group consisting of pyridylimidazoles of the formulae: ##STR7## and the pharmaceutically acceptable acid addition salts thereof, wherein R 1  is selected from the group consisting of hydrogen, alkyl having one to three carbon atoms and amino; R 2  and R 3  are each selected from the group consisting of hydrogen, alkyl having one to three carbon atoms and phenylalkyl wherein said alkyl contains from one to three carbon atoms; and R 4  is selected from the group consisting of methyl and amino. 
     
     
       2. A compound of claim 1, formula I, wherein R 2  is hydrogen and R 3  is alkyl having from one to three carbon atoms. 
     
     
       3. The compound of claim 2 wherein R 1  is amino and R 3  is ethyl. 
     
     
       4. The compound of claim 2 wherein R 1  is hydrogen and R 3  is ethyl. 
     
     
       5. The compound of claim 2 wherein R 1  is methyl and R 3  is ethyl. 
     
     
       6. The compound of claim 2 wherein R 1  and R 3  are each ethyl. 
     
     
       7. A compound of claim 1, formula I, wherein R 2  and R 3  are each alkyl having from one to three carbon atoms. 
     
     
       8. The compound of claim 7 wherein R 1  is hydrogen and R 2  and R 3  are each methyl. 
     
     
       9. The compound of claim 7 wherein R 1  is amino and R 2  and R 3  l are each methyl. 
     
     
       10. A compound of claim 1, formula I, wherein R 2  and R 3  are each hydrogen. 
     
     
       11. The compound of claim 10 wherein R 1  is hydrogen. 
     
     
       12. The compound of claim 1, formula II, wherein R 4  is methyl. 
     
     
       13. The compound of claim 1, formula II, wherein R 4  is amino. 
     
     
       14. A pharmaceutical composition suitable for oral administration comprising a pharmaceutically acceptable carrier and a therapeutically-effective amount of an anti-ulcer agent wherein said agent is a compound as claimed in claim 1.